This study looks into why people with **Chronic Kidney Disease (CKD)** find exercise hard and seeks ways to help. CKD affects the kidneys, making it tough for them to work properly. People with CKD often struggle with exercise because their bodies can't manage blood pressure well during physical activity. Blood pressure (BP) can rise too much, making exercise difficult and increasing the risk of heart problems. Researchers want to understand why this happens and if treatments can help. Participants will be split into two groups, one taking sodium bicarbonate, which might help balance body chemicals, along with exercise training, while the other takes a placebo. This study will last for 12 weeks with regular exercise sessions. **Key Points:** - The study involves 120 CKD patients and 36 healthy people. - Participants will undergo exercise training, with some also taking sodium bicarbonate. - The study lasts for 12 weeks, focusing on improving exercise tolerance and BP control during exercise. *Eligibility* includes having CKD (Stages III and IV) and not regularly exercising. Those with severe CKD, certain medical conditions, or recent surgeries are excluded.